Magnetic behavior of single crystalsof the perovskite oxides LaMn1−xCoxO3

Abstract

Studies of the magnetic properties of LaMn1−xCoxO3 (x = 0.18, 0.36, 0.54) single crystals grown by the electrodeposition method are presented. Magnetization measurements versus temperature and magnetic field are performed in the temperature range from 5 to 300 K and in fields up to 5 T. It is shown that the thermomagnetic irreversibility between MFC(T) and MZFC(T), the values of the magnetic moments of the Co ions, the large positive values of the paramagnetic Curie temperature, the hysteretic character of the M(H) loops, and the large values of the coercive field at low temperatures indicate the dominance of ferromagnetic interactions in these crystals. The results of measurements are analyzed in the framework of the two-phase magnetic state model in the crystal. The blocking temperature, the volume and the number of clusters are estimated for all the crystals studied. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)